1. Field of the Invention
The present invention concerns a method for stable support of a needle (in particular an elongated needle) to be inserted into a patient, as well as a retention device for such a needle and a medical treatment device embodying the retention device and a needle.
2. Description of the Prior Art
In the medical field, minimally-invasive procedures are frequently conducted with medical instruments, in particular with needles. In addition to biopsy needles, other examination and treatment needles are known, for example for ablative tumor treatments and the like. The path to the treatment location (site) is frequently planned and or monitored using image exposures. It is known to initially insert the needle only partially in order to then produce an additional image exposure. The danger exists that the needle will fall out of the patient again or rotate in the patient, which is due to the weight of the needle that is still located extracorporeally. The use of extremely stable retention devices is disadvantageous since the patient or the organs may move.
A simple solution is to support the needle by hand or with a tool held in the hand. This is disadvantageous, however because the hand or the tool could prevent the image acquisition, for example by being located in the image acquisition path or in the image acquisition volume. The image quality can consequently decrease, or the hand directing the tool or the instrument can be exposed to irradiation. Moreover, the manual retention of the needle is not ergonomic and occupies one hand of the person holding the needle.
Another approach is the use of rigid or semi-rigid retention devices, for example robot arms. However, such retention devices must be specifically positioned and then arrested. They do not represent a good compromise between retention and flexibility. Furthermore, they constitute additional equipment in the sterile area, which raises additional problems and requires additional steps to maintain sterility. Moreover, the costs of such systems are typically very high.